<?php

/*
 * This file is part of SwiftMailer. (c) 2004-2009 Chris Corbyn For the full copyright and license information, please view the LICENSE file that was distributed with this source code.
 */

/**
 * An abstract means of reading data.
 * Classes implementing this interface may use a subsystem which requires less
 * memory than working with large strings of data.
 * 
 * @package Swift
 * @subpackage ByteStream
 * @author Chris Corbyn
 */
interface Swift_OutputByteStream {
	/**
	 * Reads $length bytes from the stream into a string and moves the pointer
	 * through the stream by $length.
	 * If less bytes exist than are requested the
	 * remaining bytes are given instead. If no bytes are remaining at all, boolean
	 * false is returned.
	 * 
	 * @param int $length        	
	 * @return string
	 * @throws Swift_IoException
	 */
	public function read($length);
	
	/**
	 * Move the internal read pointer to $byteOffset in the stream.
	 * 
	 * @param int $byteOffset        	
	 * @return boolean
	 * @throws Swift_IoException
	 */
	public function setReadPointer($byteOffset);
}
